M. Haruta, G. Sabat, Kelly E. Stecker, Benjamin B. Minkoff, M. Sussman
Science, 2014
Plant cells are immobile; thus, plant growth and development depend on cell expansion rather than cell migration. The molecular mechanism by which the plasma membrane initiates changes in the cell expansion rate remains elusive. We found that a secreted peptide, RALF (rapid alkalinization factor), suppresses cell elongation of the primary root by activating the cell surface receptor FERONIA in Arabidopsis thaliana. A direct peptide-receptor interaction is supported by specific binding of RALF to FERONIA and reduced binding and insensitivity to RALF-induced growth inhibition in feronia mutants. Phosphoproteome measurements demonstrate that the RALF-FERONIA interaction causes phosphorylation of plasma membrane H+–adenosine triphosphatase 2 at Ser899, mediating the inhibition of proton transport. The results reveal a molecular mechanism for RALF-induced extracellular alkalinization and a signaling pathway that regulates cell expansion. A signaling system important in the regulation of plant cell size during development is identified. A Peptide Finds Its Receptor Because plant cells cannot move around within the plant, developmental changes are orchestrated by changes in cell size and shape. Using quantitative phosphoproteomics, genetics, and chemical analyses, Haruta et al. (p. 408) identified a signaling chain that links a secreted peptide, RALF (rapid alkalinization factor), with its receptor kinase, FERONIA, at the cell surface. FERONIA is involved in reproductive and vegetative development–processes that require the changes in cell size initiated by RALF signaling.
Cited by 82 publications.
Field of study: Biology